SLC7A11 and breast cancer: Under either cystine-enriched or cystine-starved condition, SLC7A11 knockdown inhibited, whereas KCTD10 knockdown promoted cell viability and clonogenic survival (Fig. 5 J and K and SI Appendix, Fig. S6 J and K), suggesting that SLC7A11 promotes cell viability and survival, whereas KCTD10 inhibits them in breast cancer cells.